Interfacial electronic modulation via crystalline-amorphous vanadium‑nickel bimetallic phosphide heterointerfaces for...

Constructing well-defined crystalline-amorphous heterointerfaces in bimetallic phosphides represents a promising strategy for modulating interfacial electronic structures, yet achieving such architectures with atomic-level precision remains challenging. Herein, we reported a topological transformation from layered double hydroxide precursors to synthesize a library of nickel-based bimetallic phosphides (MNiP, M = V, Cr, Mn, Fe, Co) with programmable crystalline-amorphous interfaces. Taking vanadium‑nickel bimetallic phosphide (VNi-P) as the representative, the topological phosphidation spontaneously generated a unique heterointerface architecture, where crystalline Ni₂P nanodomains (2-5 nm) were intimately embedded within an amorphous V-containing matrix. This nanoscale interfacial coupling triggered pronounced electronic polarization, as evidenced by a downshifted Ni d-band center, an elevated average Ni oxidation state of +2.77, and substantial charge accumulation around VP bonds. Density functional theory (DFT) calculations demonstrated that these interfacial electronic modulations collectively reduced the energy barriers for reactant adsorption, α-dehydrogenation and C-OH bond formation along the benzyl alcohol oxidation pathway. Consequently, VNi-P delivered near-quantitative conversion (>99%) and exceptional selectivity toward benzoic acid at an industrially relevant current density of 200 mA cm^-2, alongside outstanding long-term durability. This work established a scalable and generalizable interface-engineering platform for designing transition metal phosphides, offering new insights into interfacial electronic coupling for selective electro-organic transformations.